IMPACT OF DEVELOPMENT ON PROTEIN UTILIZATION AND GROWTH

这个子项目是利用由NIH/NCRR资助的中心拨款提供的资源的许多研究子项目之一。子项目和调查员(PI)可能从另一个NIH来源获得了主要资金，因此可能会出现在其他CRISE条目中。列出的机构是针对中心的，而不一定是针对调查员的机构。尽管低出生体重(LBW)婴儿的营养管理在过去十年中有所改善，但大多数出生时体重为1500克的婴儿在出院时(月经后约36周)的体重低于或低于宫内标准的10%，而且许多人在成年后仍很小。虽然早期增长失败的后果尚不确定，但有证据表明，它可能导致这一人群中发育缺陷的高发。有人建议进行研究，以检验这一假设，即在有限的时期内，人类婴儿能够最大限度地利用蛋白质进行生长。根据对婴儿的有限研究和对动物的急性研究，这一时期似乎包括怀孕的后期和足月后的头几个月，但它仍然没有定义。也将在人类婴儿身上测试的推论是，在对蛋白质摄取的敏感度增强的有限时期内，最大限度地摄取蛋白质将促进早期生长，从而减少早产儿随后的生长和神经发育缺陷。总之，拟议的研究将确定是否存在一个有限的时期，在此期间，人类新生儿可以最大限度地利用蛋白质摄入量来促进生长，这是通过全身蛋白质周转来衡量的，并将定义这一时期。他们还将确定在这段有限的时间内最大限度地摄入蛋白质是否在不造成不可接受的代谢后果的情况下改善早期生长，以及这种改善的生长是否减少了随后的生长和神经发育缺陷。总体而言，预计该项目的结果将有助于进一步改善营养管理，从而有助于改善LBW婴儿的结局。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Despite improvements in nutritional management of low birth weight (LBW) infants over the past decade, most who weigh <1500g at birth, weigh less than and are shorter than the 10th percentiles of intrauterine standards at discharge (~36 wks post menstrual age) and many remain small as late as young adulthood. While the consequences of the early growth failure are not known with certainty, there is evidence that it may contribute to the high prevalence of developmental deficits in this population. Studies are proposed to test the hypothesis that there is a finite period during which the human infant is capable of maximal utilization of protein for growth. Based on limited studies in infants and acute studies in animals, this period appears to encompass the latter part of gestation and the first few months post-term but it remains undefined. Corollary hypotheses, which also will be tested in human infants, are that maximizing protein intake during this finite period of enhanced sensitivity to protein intake will improve early growth and, hence, reduce the subsequent growth and neurodevelopmental deficits of preterm infants. In toto, the proposed studies will determine if there is a finite period during which the human neonate can maximally utilize protein intake for growth as measured by whole body protein turnover and also will define this period. They also will determine if maximizing protein intake during this finite period improves early growth without imposing unacceptable metabolic consequences and if this improved growth reduces subsequent growth and neurodevelopmental deficits. Overall, the findings of this project are expected to contribute to further improvements in nutritional management and, hence, outcome of LBW infants.